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The Oswald T. Avery Collection

Excerpt from Report of the Director of the Hospital to the Corporation of the Rockefeller Institute for Medical Research, April 20, 1929 Annotation pdf (2,876,879 Bytes) ocr (62,015 Bytes)
Excerpt from Report of the Director of the Hospital to the Corporation of the Rockefeller Institute for Medical Research, April 20, 1929
This April 20, 1929 Director's Report accounted for the work conducted on pneumonia by Avery and others in the hospital over the previous year.
Item is a photocopy.
Number of Image Pages:
31 (2,876,879 Bytes)
1929-04-20 (April 20, 1929)
Cole, Rufus
Original Repository: Rockefeller Archive Center
Reproduced with permission of the Rockefeller Archive Center.
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Medical Subject Headings (MeSH):
Transformation, Bacterial
Exhibit Categories:
The "Sugar-Coated Microbe" and the Search for a Cure for Pneumonia, 1919-1929
Shifting Focus: Early Work on Bacterial Transformation, 1928-1940
Box Number: 3
Folder Number: 4
Unique Identifier:
Document Type:
Official reports
Physical Condition:
Series: Research and Discovery of the Transforming Principle, 1912-1999
SubSeries: Excerpts from the Rockefeller Institute Reports
Folder: Oct 1928 - Oct 1929
Metadata Last Modified Date:
Linked Data:
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Annotation by Joshua Lederberg:

KW:  Attempt to transform Friedlander's bacillus; transcript of
segment of report. (Klebsiella pneumoniae}.  McCarty doesn't recall
any followup.;

jl 7/30/03

:f  /j/X/avery.290420

transcript of CCAAMP, excerpt.

Rockefeller University Archives

               Report of the Director of the Hospital

                  Scientific Reports to the Board
                         April 20, 1929
                         Box 5, Vol. 17

Section VI.  p 215/227
VI.  The Reversion of "R" Friedlander bacilli to the "S" Forms, and
the Interconvertibility of Specific Types.  Numerous attempts have
been previously made to cause reversion of "R" Friedlander bacilli
to the "S" variety by the various methods which have been effective
in the case of Pneumococcus. The results of these attempts have been
uniformly negative, and the reversion of an "R" form of Friedlander's
bacillus to its original specific type had never been attained by
"in vitro" methods.

      The recent studies of Griffith have demonstrated that, under
proper conditions, "R" pneumococci may be induced to revert not only
to the "S" antecedent, but even to the "S" form of a heterologous
type.  The method he employed consists of the simultaneous injection
subcutaneously in white mice of the deposit of large quantities
of heat killed "S" organisms and small amounts of living "R" cells.
The conversion to a different type, when it does occur, is to the
type of the culture employed as vaccine.  Subsequent confirmation of
Griffith's results in this laboratory, suggested the possibility of
the reversion of "R" forms of Friedlander bacillus by the newer

     Up to the present time two sets of experiments have been
completed.  On one occasion, of six mice injected with the deposit
equivalent to 40 cc. of Type A culture heated for 30 minutes at 56-60
degree C together with 0.25 cc. of "R" organisms derived from Type B
or Type C, 3 mice yielded cultures containing both "R" and "S"
colonies.  The "S" colonies proved to be of the Type A variety.  Three
mice which received similar quantities of heat-killed bacteria alone
were sacrificed after 10 days and in none of them were any
bacteria cultivated from either the site of injection or the heart

     On a second attempt, 4 mice each were injected with the deposit
of bacilli from 30 cc. of Type A culture previously heated (30 minutes
at 56-60 degree C), together with 0.25 cc of "R" culture derived from
Type B, Type C and Group X.  Two mice of each group yielded cultures
containing both "R" and "S" colonies; all the "S" colonies isolated,
proved serologically to be of Type A.  Four mice injected with the
same quantity of Type A vaccine and 0.25 cc. of "R" cells derived from
Type A, yielded cultures composed purely of "R" colonies.  As
controls, 4 mice received the heat-killed Type A deposit alone.  They
were killed after 10 days and cultures taken from the site of
injection and from the heart blood showed no growth.

     Since previous results from this laboratory showed that Type II
Pneumococcus and Type B, Friedlander's bacillus possess similar
antigenic properties, observations were made on the reversibility of
"R" Friedlander bacilli when injected subcutaneously into white mice
together with heat-killed suspensions of pneumococcus Type II.  Three
different sets of experiments were carried out, but in no instance was
it found that Type II Pneumococcus exerted any influence on the
reversion of Friedlander's bacilli to either homologous or
heterologous types.;

jl 7/30/03